iw4x-client/deps/mongoose/examples/file-upload-multiple-posts/web_root/app.js
2024-03-07 05:13:50 -05:00

49 lines
1.5 KiB
JavaScript

// Copyright (c) 2020 Cesanta Software Limited
// All rights reserved
// Helper function to display upload status
var setStatus = function(text) {
document.getElementById('el3').innerText = text;
};
// When user clicks on a button, trigger file selection dialog
var button = document.getElementById('el2');
button.onclick = function(ev) {
input.click();
};
// Send a large blob of data chunk by chunk
var sendFileData = function(name, data, chunkSize) {
var sendChunk = function(offset) {
var chunk = data.subarray(offset, offset + chunkSize) || '';
var opts = {method: 'POST', body: chunk};
var url = '/upload?offset=' + offset + '&name=' + encodeURIComponent(name);
var ok;
setStatus(
'Uploading ' + name + ', bytes ' + offset + '..' +
(offset + chunk.length) + ' of ' + data.length);
fetch(url, opts)
.then(function(res) {
if (res.ok && chunk.length > 0) sendChunk(offset + chunk.length);
ok = res.ok;
return res.text();
})
.then(function(text) {
if (!ok) setStatus('Error: ' + text);
});
};
sendChunk(0);
};
// If user selected a file, read it into memory and trigger sendFileData()
var input = document.getElementById('el1');
input.onchange = function(ev) {
if (!ev.target.files[0]) return;
var f = ev.target.files[0], r = new FileReader();
r.readAsArrayBuffer(f);
r.onload = function() {
ev.target.value = '';
sendFileData(f.name, new Uint8Array(r.result), 2048);
};
};